I'm talking about the ordinary little party sized balloons. How much would that many helium balloons cost to buy? Has anyone actually held on to enough balloons to float away? I hope they had strong arms.
2006-07-17 13:26:31 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Let's assume 1 balloon is a sphere 20 cm (8 inches) in diameter. The radius of the balloon is 10 cm, so the volume is 4.2 liters (v = 4/3 * pi * r^3).
The ideal gas law states that 1 mole of gas (6.02 x 10^23 molecules) occupies 22.4 liters at standard temperature and pressure. So it takes 5.35 balloons to hold 1 mole of helium.
Each molecule of helium displaces 1 molecule of air, which is mostly nitrogen. Helium has a molecular weight of about 4, and nitrogen (N2) has a molecular weight of about 28. Thus each mole of displaced gas gives you a whopping 24 grams of lift, which is less than one ounce!
If you weigh 150 pounds, that's 68,000 grams. That would be
68,000 / 24 = 2834 moles of helium
2834 x 5.35 = 15,158 balloons (!!)
2006-07-17 13:44:38 · answer #1 · answered by Keith P 7 · 1⤊ 0⤋
I saw them try this on Mythbusters and it took them several hundred, or maybe it was over a thousad, big helium party balloons just to lift a little girl. I would take a whole lot more to lift a grown person.
2006-07-17 13:30:32 · answer #2 · answered by lemonlimeemt 6 · 0⤊ 0⤋
Check out the MythBusters solution- 6000 to 7000!
http://dsc.discovery.com/fansites/mythbusters/photogalleries/balloon/balloon.html
2006-07-17 13:31:07 · answer #3 · answered by ladders_to_fire 5 · 1⤊ 0⤋
as many to displace their weight plus some for rate of climb.
I sense you should not try to lift off...
2006-07-17 13:39:26 · answer #4 · answered by ppellet 3 · 0⤊ 0⤋